The Generic SSO PKCE flow used the URL ``state`` parameter as the
cache key for the PKCE ``code_verifier`` without binding the state
to the caller's browser. An attacker who pre-minted a state and
cached a verifier under it could hand the resulting login link to a
victim; the victim's auth code would then be exchanged with the
attacker's verifier on the callback, producing an access token
under the attacker's control (Login CSRF / token theft).
The non-PKCE branch is unaffected because it delegates to
fastapi-sso's ``verify_and_process``, which performs its own
session-cookie check. The PKCE branch bypasses that helper, which
is exactly the gap this commit closes.
Two-part fix in ``ui_sso.py``:
- ``get_generic_sso_redirect_response`` now sets a
``litellm_oauth_state`` cookie (HttpOnly, SameSite=Lax, 10-min TTL)
carrying the state value used in the redirect URL. The cookie is
set on the redirect response just like the existing
``litellm_cp_return_to`` cookie a few lines earlier in the file.
- ``get_generic_sso_response`` validates ``request.cookies.get(
"litellm_oauth_state")`` against ``request.query_params.get(
"state")`` via ``secrets.compare_digest`` before invoking the
PKCE token exchange. Mismatch (or either being missing) raises a
``ProxyException`` with HTTP 400.
The pre-existing TODO above the redirect logic ("state should be a
random string and added to the user session with cookie") is now
addressed and removed.
Tests cover the redirect-side cookie set, the missing-cookie reject
shape, the URL/cookie-mismatch reject shape, and the matching-cookie
happy path.
Unit Tests: Proxy DB Operations / proxy-db (auth-checks, tests/proxy_unit_tests/test_auth_checks.py tests/proxy_unit_tests/test_user_api_key_auth.py, 20, 8) (push) Has been cancelled
Unit Tests: Proxy DB Operations / proxy-db (remaining, tests/proxy_unit_tests --ignore=tests/proxy_unit_tests/test_key_generate_prisma.py --ignore=tests/proxy_unit_tests/test_auth_checks.py --ignore=tests/proxy_unit_tests/test_user_api_key_auth.py --ignore=tests/proxy_unit_tests/test_p… (push) Has been cancelled
Vertex rejects array schemas without an items field
(GenerateContentRequest.tools[*].function_declarations[*].parameters...items: missing field).
This happened for tool params containing anyOf branches like {"type": "array"}
with no items, including the case where convert_anyof_null_to_nullable
strips an empty items entry. Default missing items to {"type": "object"}
in process_items so the same default applies to bare arrays and
arrays nested inside anyOf.
